The operation of cellular mobile stations (cellular telephones, for example) is fairly well known. As those who have used cellular telephones understand, the cellular telephone system allows users greater mobility while maintaining access to the cellular and public telephone systems. With this mobility, one feature that has become increasingly popular among cellular mobile station users is the ability to operate the cellular telephone in a so-called hands-free environment. That is, ideally the cellular telephone user wishes to be able to answer incoming calls, for example, without touching the mobile station.
Presently, auto answer functions in cellular mobile stations exist. For many mobile stations, for example, auto answer functions exist by adding accessories to the mobile station and enabling the auto answering by mobile station via various feature menus.
A general understanding of the operation of a cellular telephone network is relevant to an appreciation of how the present invention utilizing auto answering in a unique environment. As background, FIGS. 1 and 2 illustrate, respectively, simplified versions of the structures employed in placing a call from a cellular mobile station (FIG. 1) and receiving a call at a cellular mobile station (FIG. 2).
In FIG. 1, the cellular mobile station 10 broadcasts a call request which is received at a base station 11. The base station 11 passes the request to base station controller 12, which communicates the message, including the destination phone number, to the mobile station switch controller 13. The mobile station switch controller 13 has as its principal function the switching of cellular telephone calls to other appropriate base stations (for cellular destination calls) or the public service telephone network 15 (for public telephone destination calls). The mobile station switching center 13 employs visiting location register 14 to register the broadcast location of cellular phone 10. If the mobile station switching center 13 determines that the cellular telephone 10 is authorized to place the phone call requested, it establishes a channel between the cellular mobile station 10 and the destination station (either cellular or PSTN, etc.) when the person receiving the call answers.
FIG. 2 illustrates the reverse of FIG. 1, that is when a call is made to the cellular mobile station 10 as the destination number. In this instance, the originating phone is in PSTN 15, which switches the call request to ground mobile station switch center 17. GMSC 17 locates the home location of the destination mobile station (in this case cellular mobile station 10) from a home location register 16. GMSC 17 then sends the call request with the home location of the mobile station 10 to the mobile station switching center 13. Switching center 13 then switches the call through base station controller 12 servicing the base station 11 in the geographic cell location of the mobile station 10. When the mobile station 10 answers, the connection channel is established and the conversation can begin.
With respect to the embodiment of FIG. 2, the connection between the telephone and the PSTN 15 and the cellular mobile station 10 will not be completed until the user of the cellular mobile station 10 answers the call (usually by hitting a button on the face of the cellular telephone 10). The mobile station 10 can employ features that would permit it to auto answer these phone calls.
A feature that is also currently available is the so-called "caller-id" feature which identifies to the cellular phone user who originated an incoming call. The destination cellular phone learns of the originators' identity through a caller-id field (containing the originator's phone identifier) which is sent to the destination phone in a call request page.